The design of alternative nonaqueous high power chemistries

In order to address power demands of mobile electronics, engineers have been relegated to the incorporation of energy storage technologies with wide disparities in energy and power performance. This paper will review and present alternative non aqueous chemistries and enabling electroactive materials that have the potential to fill a critical void in the power/energy spectrum and enable the design of new and/or improved devices. Incorporating one of the first uses of inorganic intercalation nanomaterials in energy storage, the asymmetric hybrid technology was developed in order to significantly increase the energy density of the supercapacitor, while maintaining the power and most importantly the robustness. The technology delivers 10–15 Wh/kg at 1000–2000 W/kg for over 450000 full discharge cycles. For certain applications, cycle life is not a key specification but rather high power and energy. New composites were developed to address these needs and were optimized to result in systems with 30–45 Wh/kg at upwards of 3000 to 5000 W/kg,while maintaining excellent low temperature performance and fast recharge capability. The performance of these and other alternative systems are presented relative to the active materials, composition of electrodes and electrolytes, failure modes, characterization, and cell design. PACS 81.05.2; 81.70; 84.60; 84.60.D